Combustion panel grommet

ABSTRACT

A gas turbine engine and a combustor panel assembly are disclosed. The gas turbine engine includes a combustor panel with a panel dilution hole formed therethrough, a combustor liner spaced apart from the combustor panel, wherein the combustor liner includes a liner dilution hole formed therethrough, wherein at least one of the combustor panel and the combustor liner is formed from a first material, and a grommet with a first end with a first radius, a second end with a second radius, and a continuous smooth surface between the first end and the second end, wherein the first radius is larger than the second radius, the grommet defining a flow path between the panel dilution hole and the liner dilution hole, and the grommet is formed from a second material.

BACKGROUND

The present disclosure relates to grommets for gas turbine engines, andmore particularly to grommets for use with combustors for gas turbineengines.

Dilution holes and grommets can be utilized within combustors of gasturbine engines to condition combustion gases prior to entering theturbine for reliable operation and performance. During operation, thedilution hole grommets may experience high temperatures, oxidize, andcontain features that reduce flow.

Accordingly, it is desirable to provide conditioning features thatresist high temperatures and do not restrict dilution flow.

BRIEF SUMMARY

According to an embodiment, a combustor panel assembly for use with acombustor includes a combustor panel with a panel dilution hole formedtherethrough, a combustor liner spaced apart from the combustor panel,wherein the combustor liner includes a liner dilution hole formedtherethrough, wherein at least one of the combustor panel and thecombustor liner is formed from a first material, and a grommet with afirst end with a first radius, a second end with a second radius, and acontinuous smooth surface between the first end and the second end,wherein the first radius is larger than the second radius, the grommetdefining a flow path between the panel dilution hole and the linerdilution hole, and the grommet is formed from a second material.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet has afrustroconical shape.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a ceramic matric composite.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a molybdenum alloy.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a nickel alloy.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a monolithic ceramic.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet isaffixed to the combustor panel.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet isaffixed to the combustor panel via a fastener.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet isaffixed to the combustor panel via a brazed joint.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet isaffixed to the combustor panel via a welded joint.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet isaffixed to the combustor panel via a threaded connection.

According to an embodiment, a combustor includes a combustor panel witha panel dilution hole formed therethrough, a combustor liner spacedapart from the combustor panel, wherein the combustor liner includes aliner dilution hole formed therethrough, wherein at least one of thecombustor panel and the combustor liner is formed from a first material,and a grommet with a first end with a first radius, a second end with asecond radius, and a continuous smooth surface between the first end andthe second end, wherein the first radius is larger than the secondradius, the grommet defining a flow path between the panel dilution holeand the liner dilution hole, and the grommet is formed from a secondmaterial.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet has afrustroconical shape.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a ceramic matric composite.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a molybdenum alloy.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a nickel alloy.

According to an embodiment, a gas turbine engine includes a combustor,including a combustor panel with a panel dilution hole formedtherethrough, a combustor liner spaced apart from the combustor panel,wherein the combustor liner includes a liner dilution hole formedtherethrough, wherein at least one of the combustor panel and thecombustor liner is formed from a first material, and a grommet with afirst end with a first radius, a second end with a second radius, and acontinuous smooth surface between the first end and the second end,wherein the first radius is larger than the second radius, the grommetdefining a flow path between the panel dilution hole and the linerdilution hole, and the grommet is formed from a second material.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the grommet has afrustroconical shape.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a ceramic matric composite.

In addition to one or more of the features described above, or as analternative, further embodiments could include that the second materialis a molybdenum alloy.

Other aspects, features, and techniques of the embodiments will becomemore apparent from the following description taken in conjunction withthe drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the present disclosure isparticularly pointed out and distinctly claimed in the claims at theconclusion of the specification. The foregoing and other features, andadvantages of the present disclosure are apparent from the followingdetailed description taken in conjunction with the accompanying drawingsin which:

FIG. 1 is a schematic, partial cross-sectional view of a turbomachine inaccordance with this disclosure;

FIG. 2 is a detail view of the combustor section for use with theturbomachine of FIG. 1,

FIG. 3A is an exploded partial isometric view of the combustor panelassembly with a grommet for use with the combustor section of FIG. 2;and

FIG. 3B is a partial cross-sectional view of the combustor panelassembly with a grommet for use with the combustor section of FIG. 2.

DETAILED DESCRIPTION

Embodiments provide a grommet for use with a combustor panel assembly.The grommet provides a low restriction flow path for conditioningairflow while adding high temperature resistant material to thecombustor panel assembly to allow for reliable operation and desiredperformance.

Referring to FIG. 1 a schematic representation of a gas turbine engine10 is shown. The gas turbine engine includes a fan section 12, acompressor section 14, a combustor section 16, and a turbine section 18disposed about a longitudinal axis A. The fan section 12 drives airalong a bypass flow path B that may bypass the compressor section 14,the combustor section 16, and the turbine section 18. The compressorsection 14 draws air in along a core flow path C where air is compressedby the compressor section 14 and is provided to or communicated to thecombustor section 16. The compressed air is heated by the combustorsection 16 to generate a high pressure exhaust gas stream that expandsthrough the turbine section 18. The turbine section 18 extracts energyfrom the high pressure exhaust gas stream to drive the fan section 12and the compressor section 14.

The gas turbine engine 10 further includes a low-speed spool 20 and ahigh-speed spool 22 that are configured to rotate the fan section 12,the compressor section 14, and the turbine section 18 about thelongitudinal axis A. The low-speed spool 20 may connect a fan 30 of thefan section 12 and a low-pressure compressor portion 32 of thecompressor section 14 to a low-pressure turbine portion 34 of theturbine section 18. In the illustrated embodiment, the turbine section18 can include a rotating disc assembly 35. The high-speed spool 22 mayconnect a high pressure compressor portion 40 of the compressor section14 and a high pressure turbine portion 42 of the turbine section 18. Thefan 30 includes a fan rotor or fan hub 50 that carries a fan blade 52.The fan blade 52 radially extends from the fan hub 50.

In the illustrated embodiment, the combustor section 16 can haveoperating temperatures that exceed the melting point of the materialsforming the combustor section 16 components. The combustor section 16can include dilution holes to condition combustion air.

Referring to FIG. 2, the combustor section 16 is shown. In theillustrated embodiment, the combustor section 16 includes a combustorpanel assembly 17 with a combustor liner 60 and a combustor panel 62. Inthe illustrated embodiment, the combustor liner 60 and the combustorpanel 62 can be formed from any suitable material. In the illustratedembodiment, the combustor panel 62 defines an annular shaped combustionchamber. Further, the combustor liner 60 is spaced apart from thecombustor panel 62 to form an air passage between the combustor panel 62and the combustor liner 60 to provide conditioning air. In certainembodiments, the combustor panel 62 and the combustor liner 60 caninclude dilution holes to condition combustion air flow.

As shown in FIGS. 3A and 3B, in the illustrated embodiment, thecombustor liner 60 includes liner dilution holes 64 and the combustorpanel 62 includes panel dilution holes 66. In the illustratedembodiment, the air exiting the compressor section 14 of the gas turbineengine 10 is typically split or bifurcated, with a portion of thecompressed air being used for combustion, and a portion of thecompressed air being directed to the liner dilution holes 64 and thepanel dilution holes 66 for conditioning. In the illustrated embodiment,the liner dilution holes 64 and the panel dilution holes 66 can receiveconditioning airflow and provide conditioning airflow to combustorcomponents. In certain embodiments, the panel dilution holes 66 receiveairflow from the liner dilution holes 64.

In certain embodiments, the combustor panel 62 includes an alignmentstud 68. Similarly, in certain embodiments, the combustor liner 60includes an alignment hole 69. In certain embodiments, the alignmenthole 69 can receive the alignment stud 68 to facilitate alignment andinstallation. Further, the use of the alignment hole 69 with thealignment stud 68 can allow for the liner dilution holes 64 to bealigned with the panel dilution holes 66.

Referring to FIGS. 3A and 3B, a grommet 70 for use with the combustorpanel assembly 17 is shown. In the illustrated embodiment, the grommet70 includes an upper radius 72, a lower radius 74, an inner surface 76and an outer surface 78. In the illustrated embodiment, the grommet 70can be disposed within the liner dilution hole 64 and the panel dilutionhole 66 to provide a smooth continuous flow path for the conditioningair flow. The use of the grommet 70 can minimize flow restrictions forconditioning airflow while providing high-temperature resistance withinthe combustor section 16.

In the illustrated embodiment, the grommet 70 is formed from a differentmaterial than the combustor panel 62 and the combustor liner 60. Incertain embodiments, the grommet 70 is formed from a ceramic matrixcomposite. In certain embodiments, the grommet 70 is formed frommonolithic ceramics. In certain embodiments, the grommet 70 is formedfrom molybdenum alloys. In certain embodiments, the grommet 70 is formedfrom nickel alloys. Advantageously, the material of grommet 70 isselected to prevent melting or cracking of the grommet 70. Further, incertain embodiments, the materials of the grommet 70 are selected tohave a low thermal mass to minimize stored thermal energy. Further, thematerial of grommet 70 can prevent the formation of oxidation.

In the illustrated embodiment, the grommet 70 is generally shaped tosmoothly direct air from the outside the combustor liner 60, through theliner dilution hole 64 and through the panel dilution hole 66.

In certain embodiments, the grommet 70 is fastened to the combustorpanel 62 via the panel dilution hole 66. In certain embodiments, apressure differential keeps the grommet 70 attached to the combustorpanel 62. In other embodiments, the grommet 70 is fastened to thecombustor liner 60 or a combination of the combustor panel 62 and thecombustor liner 60. In certain embodiments, the grommet 70 is fastenedvia fasteners, such as nuts, bolts, etc., brazing, welding, or athreaded connection.

In the illustrated embodiment, the geometry of the grommet 70 reducesflow restriction for conditioning flows entering the liner dilution hole64 and the panel dilution hole 66, allowing for less work to beperformed by the compressor of the engine. In the illustratedembodiment, the grommet 70 generally has a frustroconical shape, with anupper radius 72 and a lower radius 74. In the illustrated embodiment,the grommet 70 converges from the larger upper radius 72 to the smallerlower radius 74. In the illustrated embodiment, the inner surface 76provides a continuous, uninterrupted flow path that transitions from thelarger upper radius 72 to the smaller lower radius 74. In theillustrated embodiment, the outer surface 78 can interface with thecombustor liner 60, the liner dilution hole 64, the combustor panel 62,and the panel dilution hole 66.

Advantageously, the materials and geometry of the grommet 70 allow formore efficient engine operation, increased durability, highertemperature operation, prevents thermal and mechanical failure, andallows for increased “time on wing” metrics.

While the present disclosure has been described in detail in connectionwith only a limited number of embodiments, it should be readilyunderstood that the present disclosure is not limited to such disclosedembodiments. Rather, the present disclosure can be modified toincorporate any number of variations, alterations, substitutions orequivalent arrangements not heretofore described, but which arecommensurate with the spirit and scope of the present disclosure.Additionally, while various embodiments of the present disclosure havebeen described, it is to be understood that aspects of the presentdisclosure may include only some of the described embodiments.Accordingly, the present disclosure is not to be seen as limited by theforegoing description, but is only limited by the scope of the appendedclaims.

What is claimed is:
 1. A combustor panel assembly for use with a combustor, the combustor panel assembly comprising: a combustor panel with a panel dilution hole formed therethrough; a combustor liner spaced apart from the combustor panel, wherein the combustor liner includes a liner dilution hole formed therethrough, wherein at least one of the combustor panel and the combustor liner is formed from a first material; and a grommet with a first end with a first radius, a second end with a second radius, and a continuous smooth surface between the first end and the second end, wherein the first radius is larger than the second radius, the grommet defining a flow path between the panel dilution hole and the liner dilution hole, and the grommet is formed from a second material.
 2. The combustor panel assembly of claim 1, wherein the grommet has a frustroconical shape.
 3. The combustor panel assembly of claim 1, wherein the second material is a ceramic matric composite.
 4. The combustor panel assembly of claim 1, wherein the second material is a molybdenum alloy.
 5. The combustor panel assembly of claim 1, wherein the second material is a nickel alloy.
 6. The combustor panel assembly of claim 1, wherein the second material is a monolithic ceramic.
 7. The combustor panel assembly of claim 1, wherein the grommet is affixed to the combustor panel.
 8. The combustor panel assembly of claim 7, wherein the grommet is affixed to the combustor panel via a fastener.
 9. The combustor panel assembly of claim 7, wherein the grommet is affixed to the combustor panel via a brazed joint.
 10. The combustor panel assembly of claim 7, wherein the grommet is affixed to the combustor panel via a welded joint.
 11. The combustor panel assembly of claim 7, wherein the grommet is affixed to the combustor panel via a threaded connection.
 12. A combustor, comprising: a combustor panel with a panel dilution hole formed therethrough; a combustor liner spaced apart from the combustor panel, wherein the combustor liner includes a liner dilution hole formed therethrough, wherein at least one of the combustor panel and the combustor liner is formed from a first material; and a grommet with a first end with a first radius, a second end with a second radius, and a continuous smooth surface between the first end and the second end, wherein the first radius is larger than the second radius, the grommet defining a flow path between the panel dilution hole and the liner dilution hole, and the grommet is formed from a second material.
 13. The combustor of claim 12, wherein the grommet has a frustroconical shape.
 14. The combustor of claim 12, wherein the second material is a ceramic matric composite.
 15. The combustor of claim 12, wherein the second material is a molybdenum alloy.
 16. The combustor of claim 12, wherein the second material is a nickel alloy.
 17. A gas turbine engine, comprising: a combustor, including: a combustor panel with a panel dilution hole formed therethrough; a combustor liner spaced apart from the combustor panel, wherein the combustor liner includes a liner dilution hole formed therethrough, wherein at least one of the combustor panel and the combustor liner is formed from a first material; and a grommet with a first end with a first radius, a second end with a second radius, and a continuous smooth surface between the first end and the second end, wherein the first radius is larger than the second radius, the grommet defining a flow path between the panel dilution hole and the liner dilution hole, and the grommet is formed from a second material.
 18. The gas turbine engine of claim 17, wherein the grommet has a frustroconical shape.
 19. The gas turbine engine of claim 17, wherein the second material is a ceramic matric composite.
 20. The gas turbine engine of claim 17, wherein the second material is a molybdenum alloy. 